Removal of ions from a fluid, such as occurs in the desalination of water, is commonly effected by evaporative techniques which require considerable energy. The water must be heated to steam, the steam drawn off and condensed. While such techniques may be acceptable for producing relatively small amounts of water, the large latent heat of vaporization of water renders such techniques impractical for desalinating large quantities of water, for example, for agricultural or industrial use.
Evaporative techniques are further impractical under conditions where significant amounts of fuel are unavailable, or it is impractical to generate the heat needed for desalination. For example, survivors from a shipwreck or a plane crash stranded on the ocean cannot normally boil water to steam and condense the steam on a raft. There is a need for an ion separation and removal device that operates more economically than evaporative techniques and is useable under primitive or adverse conditions.